**4. Results and discussion**

*Current Topics in Biochemical Engineering*

**94**

**Figure 6.**

**Figure 5.**

**3.9 Thermography**

To obtain the IR images, first, the 820 nm wavelength laser was fastened to the support for it to aim directly to the sample (**Figure 6a**). Then the Digital IR

*Images of the installation of the (a) 820 nm wavelength laser, (b) non-contact digital IR thermometer, (c) connection to the multi-channel laser source, and (d) selection of the channel with the desired wavelength.*

*Images of the shell growing process. (a) Gold hydroxide solution, (b) gold hydroxide + seeded silica, (c) gold* 

*hydroxide + seeded silica + formaldehyde, and (d) solution after 10 min of reaction.*
